公开(公告)号：US20140286067A1

公开(公告)日：2014-09-25

申请号：US14198034

申请日：2014-03-05

Applicant: Hitachi, Ltd.

Inventor： Masami OHNISHI ,  Takeshi TOKUYAMA

IPC: H02M7/46 ,  H02M7/53

CPC classification number: H02M7/53 ,  H01L24/36 ,  H01L24/40 ,  H01L2224/40245 ,  H01L2224/84801 ,  H01L2924/00014 ,  H01L2924/12032 ,  H01L2924/13055 ,  H01L2924/13091 ,  H02M1/34 ,  H02M7/003 ,  H01L2924/00 ,  H01L2224/37099

Abstract: An inverter device includes; a switching element; a plurality of flyback diodes each connected in parallel with the switching element; a first conductor plate connected to anode terminals of the flyback diodes and to one side of the switching element; and a second conductor plate connected to cathode terminals of the flyback diodes and to the other side of the switching element. Each of the flyback diodes is formed in a polygonal shape, and the two flyback diodes in each pair of the flyback diodes that are arranged in mutually adjacent positions are arranged so that a vertex of one opposes a vertex of the other.

Abstract translation: 逆变器装置包括： 开关元件; 多个反激二极管，各自与开关元件并联连接; 连接到回扫二极管的阳极端子和开关元件的一侧的第一导体板; 以及连接到回扫二极管的阴极端子和开关元件的另一侧的第二导体板。 每个回扫二极管形成为多边形，并且布置在相互相邻位置的每对反激式二极管中的两个反激二极管被布置成使得顶点与另一个的顶点相反。

公开(公告)号：US20240106553A1

公开(公告)日：2024-03-28

申请号：US18244471

申请日：2023-09-11

Applicant: Hitachi, Ltd.

Inventor： Ken TAKEI ,  Yuichi IGARASHI ,  Masami OHNISHI

IPC: H04B17/391 ,  H04W24/06 ,  H04W64/00

CPC classification number: H04B17/3912 ,  H04W24/06 ,  H04W64/003

Abstract: The position of a movable body is estimated without requiring the movable body to recognize and report its own position, and the position is reflected in a structural model constructed in a computer for the purpose of wireless communication environment evaluation. Provided is a wireless communication environment evaluation method including using an information processing device that includes a central processing unit, an output device, an input device, and a memory device, and that is configured to provide a computational resource, in which the information processing device is configured to construct a structural model of an electromagnetic wave scatterer in the computational resource, calculate a characteristic of an electromagnetic field by using the structural model and a ray that simulates a radio wave traveling in a real space, and obtain, on the basis of a result of the calculation using a first structural model corresponding to a real space including a first object and excluding a second object and electromagnetic wave vector measurement data on a real space including the first object and the second object, position information on a position of the second object.

公开(公告)号：US20230396348A1

公开(公告)日：2023-12-07

申请号：US18201227

申请日：2023-05-24

Applicant: Hitachi, Ltd.

Inventor： Ken TAKEI ,  Masami OHNISHI ,  Ryosuke FUJIWARA

IPC: H04B17/391 ,  H04W24/06

CPC classification number: H04B17/3912 ,  H04W24/06

Abstract: An objective of the present invention is to use a calculation model to calculate, with good accuracy, behavior of electromagnetic waves within an actual service area. Provided is a radio environment evaluation method that includes constructing, within a computer resource, a structural model for an electromagnetic wave scatterer, and when calculating a characteristic of an electromagnetic field by using the structural model and a ray that simulates a radio wave traveling straight through real space, correcting, in accordance with electromagnetic wave vector measurement data for real space, a state of a polygon included in the structural model.